Field of the Invention
The present invention relates to a sample holder and an electron microscope.
Description of Related Art
An energy dispersive X-ray spectrometer (EDS spectrometer or simply EDS) is known as an elemental analyzer equipped in a scanning electron microscope (SEM) or in a transmission electron microscope (TEM).
An EDS has a semiconductor detector. When X-rays generated from a sample are detected, the semiconductor detector (X-ray detector) is disposed near the sample (see, for example, JP-A-2016-72005).
FIG. 13 schematically illustrates the manner in which an EDS analysis is being conducted in a transmission electron microscope. When a sample S held to a sample holder 1100 is illuminated with an electron beam EB, Bremsstrahlung occurs in the sample S. That is, electrons undergo acceleration from electric fields of atomic nuclei within the sample to thereby radiate electromagnetic waves (X-rays). If X-rays produced by Bremsstrahlung are reflected by a bottom polepiece 1013 and accepted into a semiconductor detector 1022, then the background of the resulting spectrum will increase.
If the electron beam EB impinges on the sample S, the electrons are scattered within the sample S, thus producing scattered electrons. The scattered electrons collide against the bottom polepiece 1013, generating characteristic X-rays from the bottom polepiece 1013. If characteristic X-rays emanating from other than the sample S are accepted into the semiconductor detector 1022, peaks of elements originating from other than the sample appear in the spectrum.
In EDS, in order to detect trace elements unambiguously, it is important to reduce the background. For this purpose, acceptance of unwanted X-rays such as caused by Bremsstrahlung and X-rays emanating from other than the sample into the semiconductor detector must be limited.